Form N-648 Examples: Diagnosis, Nexus, and Oath Wording

Strong Form N-648 examples share three habits: the diagnosis is described in plain functional language rather than named as a label, the nexus paragraph ties that specific condition to this specific applicant’s inability to learn or demonstrate English or civics, and the diagnostic methods section points to concrete tests, scores, or imaging. The samples below, drawn from the official USCIS form instructions and policy guidance, show what each section should look like on the page and what phrasing tends to get forms rejected.

Example Language for the Medical Diagnosis

The diagnosis field is not a place for a one-word label. Writing “dementia” or “PTSD” and moving on tells the officer nothing about how the condition operates in this patient. A usable entry names the condition, describes what it does to cognition or functioning, and states when it began, all in language a non-clinician can follow.

The official form instructions offer this example for a patient with severe intellectual disability:

“The patient’s condition is a global, lifelong impairment that severely affects cognition, language, and motor skills. Because of this impairment, the patient’s memory is deficient, the patient cannot learn new skills, and the patient is not capable of reasoning. The patient is only able to perform simple daily activities. The patient’s severe intellectual disability makes the patient incapable of learning a new language (even basic words) and demonstrating the required knowledge of U.S. history and government.”¹

Look at what the example does. It identifies the condition as global and lifelong. It lists the specific functional deficits (memory, learning, reasoning). It describes the patient’s baseline (simple daily activities only). Then it closes by connecting those deficits directly to the two naturalization requirements. That closing sentence is the bridge to the nexus section and is the pattern to imitate.

Including a DSM-5 or ICD code alongside the written description is good practice, but USCIS cannot reject a form solely because the codes are absent so long as the written description of the clinical diagnosis is adequate.² The prose does the work.

Example Language for the Nexus Explanation

The nexus explanation is where the most forms fail. USCIS wants the medical professional to explain, individually for this applicant, how the diagnosed condition prevents learning or demonstrating English, civics, or both, with enough clinical detail that the officer can see the functional link.²

Sentences like “the patient’s condition prevents learning” are not enough. The explanation needs to name the mechanism at work. Three examples of how that reads for different diagnoses:

Alzheimer’s disease: The patient’s progressive memory loss has destroyed her ability to form new memories. She cannot retain information presented to her for more than a few minutes. During testing, she was unable to recall any of three words after a five-minute delay. This deficit makes it impossible for her to study and retain civics facts or learn new English vocabulary.
Severe PTSD: The patient experiences intrusive flashbacks, hypervigilance, and severe anxiety triggered by unfamiliar environments and authority figures. During the clinical interview, he became visibly distressed and was unable to respond to basic questions. These symptoms would prevent him from participating in an interview setting, and his chronic sleep disruption and inability to concentrate have made language acquisition impossible despite years of effort.
Stroke with aphasia: The patient suffered a left-hemisphere stroke that damaged the brain’s language processing centers. She has expressive aphasia, meaning she understands some spoken language but cannot produce coherent speech or write legibly. These deficits directly prevent her from meeting the speaking, reading, and writing components of the English requirement.

Each example follows the same shape. It names the underlying mechanism (memory encoding failure, trauma symptomology, damage to language centers), gives a concrete observation from the examination, and then states which specific naturalization requirement the mechanism defeats. If the applicant needs only the English exception, the nexus should say so and not sweep in civics without reason. A medical professional who checks every box by default weakens the form.²

The nexus should also address why USCIS’s reasonable accommodations would not solve the problem. USCIS offers extended time, large-print materials, sign language interpreters, and oral alternatives to the writing test.³ For an applicant with profound memory loss, sample language might read: “Extended testing time and large-print materials would not address the patient’s inability to encode new information. No amount of additional time allows retention of material the patient cannot store in memory.” That single sentence closes off the question an officer would otherwise ask.

Example Language for Diagnostic Methods

The methods section shows the diagnosis rests on evidence, not on a brief chat. The official instructions give this example for a congenital condition:

“The patient was diagnosed in utero through a Chorionic Villus Sampling (CVS). CVS is a test done during early pregnancy that can identify certain genetic disorders or chromosomal birth defects, such as ‘Severe intellectual disabilities.’ I confirmed this by reviewing medical records provided by the patient.”¹

For conditions diagnosed in adulthood, the same principle applies: name the actual tools used. Compare two versions of the same entry.

Thin: “Clinical interview and review of records.”

Specific: “Administration of the Montreal Cognitive Assessment, on which the patient scored 12 out of 30, indicating significant cognitive impairment, combined with review of MRI imaging from January 2025 showing hippocampal atrophy.”

The second version gives the officer something to weigh. Cognitive assessments, brain imaging, psychiatric evaluations, and observations from the in-person or telehealth examination all belong here, with dates and results where possible.

Example Language for the Oath of Allegiance Section

The disability exception waives the English and civics tests, but it does not automatically waive the Oath of Allegiance. That is a separate waiver with its own justification.⁴ An applicant who cannot understand or communicate an understanding of the oath’s meaning needs the medical professional to explain that inability specifically.

If the same form covers both, the professional should treat the oath inability as its own paragraph rather than folding it into the testing nexus. Sample framing: “In addition to the inability to meet the English and civics requirements described above, the patient’s severe intellectual disability prevents her from understanding the concepts of allegiance, renunciation, and support of the Constitution contained in the Oath of Allegiance. She cannot process abstract concepts or communicate consent to obligations she does not comprehend.” Keeping the two inabilities distinct on the page makes it easier for the officer to grant both.⁴

Wording Patterns That Get N-648 Forms Rejected

Reviewing officers see the same weaknesses over and over. The wording problems that most commonly sink a form:

Missing nexus. The form names a diagnosis but never connects it to this applicant’s inability to meet the requirements. This is the single most common deficiency.²
Boilerplate that could apply to any patient with the same diagnosis. Officers are trained to recognize “one size fits all” language and treat it as insufficient.
Hedging verbs. “May affect,” “might interfere,” “could prevent.” A certification signed under penalty of perjury needs to speak in the indicative: does, prevents, is unable.
Vague methods. “Clinical interview and record review” without saying which records, which interview questions, or which standardized instruments were used.
Silence on drug use. The professional must attest that the impairment is not related to illegal drug use; leaving that field blank creates a problem.²
Conflicts with the file. Statements that contradict the applicant’s earlier immigration medical exam, N-400 answers, or prior interviews will draw follow-up questions.

Signing and Timing Details That Affect the Writing

Only a licensed medical doctor, doctor of osteopathy, or clinical psychologist can complete and sign the form.⁵ A form otherwise well written but signed by a nurse practitioner or licensed clinical social worker will be rejected regardless of content. The signing professional must have examined the applicant in person or, where state law allows, through a real-time telehealth session.⁶ The written examples in the diagnostic methods section should reflect that a live evaluation actually occurred.

The completed form must be signed no more than 180 days before Form N-400 is filed.¹ If drafting takes weeks between examination and signature, that gap eats into the 180-day window. USCIS will accept a later submission when extenuating circumstances explain it, such as a disability that developed or worsened after the N-400 was already filed, but the applicant should be ready to explain the delay in writing.²

1
U.S. Citizenship and Immigration Services. Instructions for Medical Certification for Disability Exceptions
2
U.S. Citizenship and Immigration Services. USCIS Policy Manual – Medical Disability Exception (Form N-648)
3
U.S. Citizenship and Immigration Services. USCIS Policy Manual – Types of Accommodations
4
U.S. Citizenship and Immigration Services. USCIS Policy Manual – Oath of Allegiance Modifications and Waivers
5
U.S. Citizenship and Immigration Services. Information for Medical Professionals Completing Form N-648
6
U.S. Citizenship and Immigration Services. N-648, Medical Certification for Disability Exceptions